The motion kit driver will consist of a Custom Firmware plugin /prx), one for < 3.71 and one for above and a small SDK for developers.The driver will allow you to use the motion kit in any homebrews or UMD games, even if they were not specifically written for it, by simple means of forwarding motion kit input to the PSP buttons. The buttons are user configurable and can be chosen per homebrew/UMD, so you have different configurations for every game. With this, you can even control the XMB by pure motion input.
Developers on the other side, get a useful interface to handling motion kit input without having to care about SIO initialization or similar themself.For more information, read here too: http://www.fx-world.org/wordpress/?p=44